An exploratory research is proposed to develop micro-sensors that can be used as implant microphones to sense the sound vibration of the middle ear structure and to convert it into high quality electrical signals for the input of implant cochlear or middle-ear hearing systems. The proposed project will bring together the medical and engineering investigators to integrate the expertise in hearing physiology, sensor design, micro-machining technology, and micro-electronics with the aims: (1) to study novel sensor mechanisms that can function in the middle ear chamber without packaging and presents minimum loading [less than 10 mg] to the ossicles; (2) to develop design and fabrication processes of the implantable sensor that can detect the sound vibration of ossicles without alter the structure and does not require critical positioning of the sensor in the middle ear chamber; (3) to design and fabricate the micropowered electronics circuit to amplify the sound signal to a level that can be coupled to the input of the existing cochlear implant system or can be connected to an implant middle ear actuator to provide adequate hearing aid function; and (4) to evaluate the prototype sensor and the bio-electronic microphone in the laboratory and in the temporal bone expedients to assess the feasibility of pursuing the future development of totally implantable cochlear system and middle ear hearing device. When the result of this exploratory study justifies, a continuation proposal will be submitted for further study to develop and fabricate the clinical version of micro-sensors and to evaluate them in animals as well as selected clinical cases for the development of totally implantable cochlear systems or middle ear hearing devices.